Effects of selection harvest and prescribed fire on the soil nitrogen status of ponderosa pine forests

Fire exclusion policies have affected stand structure and wildfire hazard in north American ponderosa pine forests. Wildfires are becoming more severe in stands where trees are densely stocked with shade-tolerant understory trees. Although forest managers have been employing fuel treatment techniques to reduce wildfire hazard for decades, little scientific evidence documents the success of treatments in reducing fire severity. Our research quantitatively examined fire effects in treated and untreated stands in western United States national forests. Four ponderosa pine sites in Montana, Washington, California and Arizona were selected for study. Fuel treatments studied include: prescribed fire only, whole-tree thinning, and thinning followed by prescribed fire. On-the-ground fire effects were measured in adjacent treated and untreated forests. We developed post facto fire severity and stand structure measurement techniques to complete field data collection. We found that crown fire severity was mitigated in stands that had some type of fuel treatment compared to stands without any treatment. At all four of the sites, the fire severity and crown scorch were significantly lower at the treated sites. Results from this research indicate that fuel treatments, which remove small diameter trees, may be beneficial for reducing crown fire hazard in ponderosa pine sites.

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Exotic Plant Species Diversity: Influence of Roads and Prescribed Fire in Arizona Ponderosa Pine Forests

Rangeland Ecology & Management ◽

10.2111/07-059.1 ◽

2008 ◽

Vol 61 (3) ◽

pp. 284-293 ◽

Cited By ~ 17

Author(s):

James F. Fowler ◽

Carolyn Hull Sieg ◽

Brett G. Dickson ◽

Victoria Saab

Keyword(s):

Species Diversity ◽

Plant Species ◽

Prescribed Fire ◽

Ponderosa Pine ◽

Plant Species Diversity ◽

Pine Forests ◽

Exotic Plant ◽

Exotic Plant Species ◽

Ponderosa Pine Forests

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Prescribed fire effects on bark beetle activity and tree mortality in southwestern ponderosa pine forests

Forest Ecology and Management ◽

10.1016/j.foreco.2007.08.026 ◽

2008 ◽

Vol 255 (1) ◽

pp. 119-128 ◽

Cited By ~ 70

Author(s):

C.R. Breece ◽

T.E. Kolb ◽

B.G. Dickson ◽

J.D. McMillin ◽

K.M. Clancy

Keyword(s):

Bark Beetle ◽

Prescribed Fire ◽

Ponderosa Pine ◽

Tree Mortality ◽

Fire Effects ◽

Pine Forests ◽

Ponderosa Pine Forests

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Effects of Prescribed Fire on Winter Assemblages of Birds in Ponderosa Pine Forests of Northern Arizona

The Southwestern Naturalist ◽

10.1894/mh-47.1 ◽

2010 ◽

Vol 55 (1) ◽

pp. 22-28 ◽

Cited By ~ 1

Author(s):

Theresa L. Pope ◽

William M. Block

Keyword(s):

Prescribed Fire ◽

Ponderosa Pine ◽

Pine Forests ◽

Ponderosa Pine Forests ◽

Northern Arizona

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Developing resilient ponderosa pine forests with mechanical thinning and prescribed fire in central Oregon's pumice region

Canadian Journal of Forest Research ◽

10.1139/x09-044 ◽

2009 ◽

Vol 39 (6) ◽

pp. 1171-1185 ◽

Cited By ~ 10

Author(s):

Matt D. Busse ◽

P.H. Cochran ◽

William E. Hopkins ◽

William H. Johnson ◽

Gregg M. Riegel ◽

...

Keyword(s):

Plant Diversity ◽

Prescribed Fire ◽

Ponderosa Pine ◽

Prescribed Burning ◽

Stand Structure ◽

Forest Vegetation ◽

Pine Forests ◽

Production Plant ◽

Ponderosa Pine Forests ◽

Combined Use

Thinning and prescribed burning are common management practices for reducing fuel buildup in ponderosa pine forests. However, it is not well understood if their combined use is required to lower wildfire risk and to help restore natural ecological function. We compared 16 treatment combinations of thinning, prescribed fire, and slash retention for two decades across a site quality gradient of second-growth pine stands, measuring changes in forest vegetation growth, structure, and composition. Thinning alone doubled the diameter growth increment of ponderosa pine, moderately stimulated shrub production, and resulted in lower tree mortality compared with unthinned plots. In contrast, repeated fire alone did not substantially alter stand structure or increase tree vigor, herbaceous production, or plant diversity. The combined use of thinning and repeated burning reduced shrub cover, yet produced no changes in herbaceous production, plant diversity, stand structure, or tree vigor compared with thin-only treatments. Additional findings identified (1) inconsequential effects of thinning residues on site productivity, (2) the need for multiple entries of prescribed fire if the abatement of shrubs is required, (3) the ineffectiveness of repeated burning to stimulate plant growth, and (4) that the thinning treatment served as an effective surrogate to fire for managing central Oregon forest vegetation.

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